System and method for control of power distribution networks

ABSTRACT

A system for controlling a multi-feed power distribution network includes: a first controller configured to control operation of a first network sector, the first controller configured to, in response to a topology change in the first network sector causing a change in a location from which power is supplied to at least one affected network segment, transmit a message identifying the at least one affected network segment from the first controller to the network without prior knowledge of any other controllers; and at least one second controller configured to control operation of the at least one second network sector, the second controller configured to receive the message, exchange configuration information regarding the at least one affected segment with the first controller, and automatically update the second configuration data of the second controller based on the configuration information received from the first controller to reflect the topology change.

BACKGROUND OF THE INVENTION

The subject matter disclosed herein relates to systems and applicationsfor controlling power distribution networks with multiple feeds from oneor more substations.

Electrical power distribution networks (i.e., grids) generally consistof multiple segments tied together via switches and other field devices,and are generally fed from one or more sources. Such networks may useactive devices which can sense conditions in power circuits formed inthe networks and can distinguish between the various segments (e.g.controlled switches, reclosers, etc.). Many control systems for morecomplex grids, such as mesh-like grids, require centralized distributionmanagement systems (DMS) or central controllers that control operationof all substations. Such centralized solutions require dedicatedresources for deployment and maintenance, such as specific equipment andhuman skill sets.

Alternatively, control systems may utilize entirely distributed logiccontrollers for complex grids, with all such controllers locateddirectly at the sectionalizing points of the power grid (“in field”).However, such distributed logic control systems generally require theuse of the same type of control devices, often from the same supplier,across the entire distribution power grid. Such “peer to peer‘intelligent’” solutions for field devices, which may be defined asneighbor to neighbor communications exclusively among such in fieldcontrollers, generally do not require dedicated controllers insubstations, but rely on some sort of identical “smart” device beingdeployed at every field location, and quite often rely on specificcommunications protocols and mediums for field devices. In addition, theinclusion of new control devices and/or field devices due to changes innetwork topology may require the reconfiguration of existing controldevices.

Other systems may include one or more control devices associated withrespective substations. Such control devices generally must bepre-configured to be aware of one another so that data could beexchanged there between. Changes in previously deployed controllerconfigurations are required every time a new controller is added. Inaddition, in instances such as fault isolation and restorationprocesses, changes that result in a change in power system topologiesand power flow direction may cause affected controllers to be preventedfrom responding to additional topology changes.

BRIEF DESCRIPTION OF THE INVENTION

According to one aspect of the invention, a system for controlling amulti-feed power distribution network, the network including a firstnetwork sector that includes a first plurality of devices connected to afirst power source and at least one second network sector that includesa second plurality of devices connected to a second power source,includes: a first controller configured to control operation of thefirst network sector and including first configuration data representinga first network sector topology, the first controller configured to, inresponse to a topology change in the first network sector causing achange in a location from which power is supplied to at least oneaffected network segment, transmit a message identifying the at leastone affected network segment from the first controller to the networkwithout prior knowledge of any other controllers; at least one secondcontroller configured to control operation of the at least one secondnetwork sector and including second configuration data representing asecond network sector topology, the second controller configured toreceive the message without prior knowledge of any other controllers,exchange configuration information regarding the at least one affectedsegment with the first controller, and automatically update the secondconfiguration data of the second controller based on the configurationinformation received from the first controller to reflect the topologychange.

According to another aspect of the invention, a method of controlling amulti-feed power distribution network including a plurality of devices,the network including a first network sector that includes a firstplurality of devices connected to a first power source and at least onesecond network sector that includes a second plurality of devicesconnected to a second power source, includes: in response to a topologychange in the first network sector controlled by a first controllerincluding first configuration data representing a first network sectortopology, the topology change causing a change in a location from whichpower is supplied to at least one affected network segment, transmittinga message identifying the at least one affected network segment from thefirst controller to the network without prior knowledge of any othercontrollers; receiving the message by at least one other controllerconfigured to control the at least one second network sector, withoutprior knowledge of any other controllers, the at least one othercontroller including second configuration data representing a secondnetwork sector topology; exchanging configuration information regardingthe at least one affected segment between the first controller and theat least one other controller; and automatically updating the secondconfiguration data of the at least one other controller based on theconfiguration information received from the first controller to reflectthe topology change.

These and other advantages and features will become more apparent fromthe following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description of the figures is not intended to be, andshould not be interpreted to be, limiting in any way.

FIG. 1 is an illustration of an electrical power distribution network ina pre-fault state and its associated devices.

FIG. 2 is an illustration of the electrical power distribution networkof FIG. 1 after a network topology change and its associated devices.

FIG. 3 is a flow diagram illustrating an embodiment of a method ofcontrolling a multi-feed power distribution network.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments of systems and methods for describing andcontrolling power distribution networks are described herein. Thesystems include logic controllers, each overseeing a plurality ofdevices and capable of data exchange between controllers, and multiplefeed power network topologies. The systems and methods perform variousfunctions, including automatic self-discovery or identification ofcontrollers and automatic discovery of network configuration changes.Such identification allows controllers to continue to operate after oneor more topology changes deviating from an initial topology layout. Inone embodiment, the controllers are each associated with a respectivenetwork sector having a topology including one or more nodes or segmentsoperably connected to at least one power source. In one embodiment, atleast one controller is configured to establish ad-hoc automaticcommunication with one or more other controllers in response to a changein the at least one controller's network sector topology so that the atleast one controller and affected other controllers can automaticallylearn or update their respective configurations to reflect changes intheir respective sector topologies. Such updates in the respectiveconfigurations, in one embodiment, result in configurations that wouldbe the same as if a human operator manually configured the controllersto reflect the changed topology. The controllers may reside in, controland/or otherwise be associated with one or more power distributionsubstations.

In one embodiment, the controllers are configured to periodically orcontinuously monitor their respective sectors by observing fieldequipment status and configuration, to detect changes in theirrespective topologies. In one embodiment, the controllers are configuredto monitor their respective topologies after a topology change to detectadditional changes and/or restore their respective sectors to a previoustopology. In the case of restoration of a network sector to an initialor previous topology, the respective controller may be configured torestore its configuration to reflect initial or previous topologies.

The systems and methods described herein allow for automaticself-discovery of controllers within a network, as well as automaticcontroller configuration changes in response to power network topologychanges. The systems and methods further allow automation functions inthe controllers to continue operating after one or multiple topologychanges from an initial configured layout. The systems and methods mayalso allow the controllers to automatically restore their respectiveconfigurations to previous configurations as the network topology isrestored to a previous topology or as an operator requires.

Various embodiments of a control application, such as computer programs,are described which may be provided as modules in existing networkcontrol applications. Embodiments of the control application may alsoreside in modules located within distribution network control andmanagement systems and servers. When equipped with the controlapplication, and any suitable communication protocols and interfaces forinteraction with field devices, the control application may provide fulldistribution automation (DA) without the need for dedicated mastercontrollers, and allow for changes in the network topology and/orexpansion of the distribution network control without the need forextensive and potentially labor intensive changes to controllerconfigurations or software.

With initial reference to FIG. 1, an exemplary power distributionnetwork is generally indicated at 100. The power distribution network100 includes a plurality of substations 10, 20 and 30, each of which isassociated with one or more feeders, shown as 11, 12, 13, 21, 22 and 31.An example of a substation includes a distribution substation configuredto transfer power from one or more transmission systems (e.g., ahigh-voltage transmission line or network) to one or more sectors of thenetwork 100. Each substation 10, 20 and 30 includes one or more powersources or feeders 11, 12, 13, 21, 22 and 31. Each substation 10, 20, 30may also include one or more circuit breakers, i.e. substation circuitbreakers (or simply “breakers”), 301, 311, 316, 327, 328 and 340, eachof which is connected to one of feeders 11, 12, 13, 21, 22 and 31. Forthe benefit of this text, substation breakers may also be described as“roots”. As used herein, the term “feeder” refers to a powerdistribution line or other conductor that provides power to one or moreportions of the network 100. In the present exemplary embodiment shownin FIG. 1, substation 10 is associated with feeders 11, 12 and 13, eachof which are connected to breakers 301, 316 and 328 respectively.Substation 20 is associated with feeders 21 and 22, each of which areconnected to breakers 311 and 327 respectively. Substation 30 isassociated with feeder 31, which is connected to breaker 340. Althoughonly three substations are depicted in this example, the network 100 mayinclude any number of substations, each of which may include any numberof feeders.

In one embodiment, the power distribution network 100 is part of ahierarchical transmission and distribution network. A transmissionnetwork is located at a high level hierarchy and supplies power to thedistribution network 100. Substations 10, 20, 30 are located at a midlevel hierarchy and are connected to a plurality of field deviceslocated at a low level hierarchy of the transmission and distributionnetwork. In one embodiment, the controllers are located at a hierarchylevel that is at least the level of the substations, i.e., the mid levelhierarchy, which is higher than lower hierarchy levels including “infield” locations.

Network 100 includes a plurality of nodes 301-340 located for example ata low level hierarchy, each of which affect the topology of network 100and connect portions of one or more feeders. The term “node” relates toany addressable point on network 100. Nodes 301-340 may include any typeof field device such as a circuit split, a sensor or other measurementpoint, and a controllable switch such as a circuit breaker or recloser.In one embodiment, the nodes include “non-intelligent” field devices,such as devices that do not include local controllers. The field devicesmay be field-installed devices, for example. The controllable switchesmay be either normally closed or normally open. Nodes 301-340 may becharacterized as active or passive. “Active nodes” relate to any nodesthat can be controlled to affect a topology change. Active nodes includereclosers, circuit breakers and controllable switches (including, forexample, remote-controllable switches) which do not need to have anyautomation functions related to sectionalizing and restoration. Activenodes may be capable of three-phase or individual phase control.“Passive nodes” relate to nodes including network splits or anynon-controllable items, and do not cause a topology change. Passivenodes may be accounted for because of consideration of load capacitiesdue to re-routing possibilities within the network sector. Nodes mayalso define various branches, in which the circuit formed in the networksplits into multiple additional circuits. A branch may occur as a singleor multiple phase branch. The node where the split occurs, locatedtoward the associated substation breaker, may be described as a “branchroot”.

Network 100 defines an associated “layout” or “topology”, which refersto the distribution of the connections of the network, including staticand geographical distributions, as well as the number, type anddistribution of nodes in the network 100. Network 100 may also bedivided into one or more “segments”, which refer to single nodes, groupsof connected nodes and/or portions of the feeder located betweensignificant active or passive network nodes. Depending on the layout,segments may be capable of accepting power from multiple feeders acrossmultiple substations. Each segment may have an associated configured“load capacity”, which represents the maximum load that can be handledby the segment.

Referring again to FIG. 1, in the present exemplary embodiment, nodes301-340 include passive network nodes, normally closed switches,normally open switches, and sensors. There is no pre-configured limit tothe number of nodes. Nodes 302, 303, 307, 309, 317, 319, 321, 325, 326,329, 333, 334 and 338 are normally closed switches, which may be opened,for example, to isolate a faulted segment. Nodes 305, 312, 313, 323, 335and 337 are normally opened switches, which act to prevent cross powertransmission and define the sectors of network 100. Nodes 304, 306, 308,310, 315, 318, 320, 322, 324, 330, 332, 336 and 339 are passive networknodes, and nodes 314 and 331 are sensors. The layout of network 100, andthe particular configuration of types and numbers of nodes shown in thepresent embodiment are merely exemplary. The system and methodsdescribed herein are applicable to any power distribution network havingany desired topology, and any number, type and configuration of nodes.

Network 100 also includes a plurality of sectors, each of which may befed by an individual feeder, and each of which has an associated layoutor topology. The term “sector” relates to a distribution sub-networkassociated with a finite number of active nodes, such as breakers,switches and reclosers. Sectors may also be referred to as “powerareas”. The topology of a sector refers to the numbers, types andrelative positions of nodes connected to or in communication with acontroller and/or the controller's power supply. Each sector may beassociated with an individual feeder or with multiple feeders. In oneembodiment, each sector includes all of the segments between a singlebreaker in a substation connected to a single feeder and all normallyopen switches. The “edge” of a sector refers to the breakers in asubstation and the normally open switches. In the present example shownin FIG. 1, network 100 includes six sectors 211, 212, 213, 221, 222 and230, each associated with an individual feeder and bounded by asubstation breaker and at least one normally open switch. Nodes, such asnormally open switches, that define the edge of a sector and connectadjacent sectors may be referred to as “edge nodes”.

In the present example, shown in FIG. 1, all segments are three-phase,i.e., there are no single-phase circuits. However, the controlapplication and method described herein is capable of single-phaseprocessing, and thus can be applied to non-three-phase networks such assingle-phase networks.

The position of various nodes, substations, or other components innetwork 100 are described in relation to one another, and may bedescribed in relation to their position on a network path in relation toother nodes, breakers, feeders or substations. For example, a first nodedescribed as being “before” or “previous” to a second node, “preceding”the second node or “upstream” from the second node, indicates that thefirst node is located before the second node when parsing the circuitpath from the breaker toward an edge of the sector, i.e., is locatedbetween the breaker or substation and the second node. Likewise, a firstnode described as being “the next node”, “after” or “following” a secondnode, or “downstream” from the second node, indicates that the firstnode follows the second node when parsing the circuit path from thebreaker toward an edge of the sector, i.e., is located between thesecond node and a sector edge node.

Each substation 10, 20 and 30 includes a respective controller 101, 102and 103, located at, for example, a mid level hierarchy, to controlvarious network nodes. As shown in FIG. 1, controller 101 is included insubstation 10, controller 102 is included in substation 20, andcontroller 103 is included in substation 30. In one embodiment, eachcontroller 101, 102 and 103 is a Distribution Automation (DA)controller. In the present embodiment, each substation includes onecontroller. However, a substation may include more than one controllerif desired. Each controller 101, 102 and 103 may also serve as aSupervisor Control and Data Acquisition (SCADA) remote terminal unit(RTU) as needed. Each controller 101, 102 and 103 communicates in apre-configured and, in one embodiment, not dynamically changeable,client-server (master-slave) relationship with the active nodes andsensors located on power segments energized from a respectivesubstation. Each controller 101, 102 and 103 is capable of automaticallydiscovering the other controllers, without pre-configured settings, andestablishing ad-hoc exchanges of data. In one embodiment, communicationbetween controllers and nodes is accomplished by way of IP basedservices.

Each controller 101, 102 and 103 controls at least one sector connectedto a feeder or other power source. In one embodiment, a sector isdefined by its respective feeder and/or breaker and may further bedefined by one or more respective open switches. In the example shown inFIG. 1, network 100 is divided into sectors 211, 212, 213, 221, 222 and230. Sector 211 has edges defined by breaker 301 and normally openswitches 305 and 312, sector 212 has edges defined by breaker 316 andnormally open switches 312, 323 and 337, and sector 213 has edgesdefined by breaker 328 and normally open switch 335. Sectors 211, 212and 213 are controlled by controller 101. Sector 221 has edges definedby breaker 311 and normally open switches 305 and 313, and sector 222has edges defined by breaker 327 and normally open switches 313 and 323.Sectors 221 and 222 are controlled by controller 102. Sector 230 hasedges defined by breaker 340 and normally open switches 335 and 337, andis controlled by controller 103. In one embodiment, all active nodes ineach sector are pre-configured to transmit data to, and receive commandsfrom, only the sector's respective controller, and dynamicre-configuration of such communication sessions may not be possible(e.g.: due to re-orientation of radio paths).

In one embodiment, if a given substation does not include a controller,controllers in other substations may be configured to interface thesectors normally covered by the given substation, thus building“logical” controllers. This configuration may result in a fully separateinstance of the control application. Multiple sectors associated withthe same substation may be controlled by the same physical controller,although from the perspective of the control application the physicalcontroller may appear as different logical controllers.

Normally open switches may send data to and accept commands fromcontrollers on either side of the normally open switch (in the case ofmultiple feeders in the same substation, these may include “logical”controllers). If this is not possible due to communication protocol orradio paths limitations in the normally open switch device, then onedesignated controller may be exclusively in charge of that active node,by marking this in the control application configuration.

The controllers and associated control applications and methods aredescribed further herein. As an example, the features of the controllerwill be described in conjunction with controller 101. However, thefeatures are also applicable to controllers 102 and 103, as well as anyother controllers applied to any other substations and/or networks.

Controller 101 receives data from, and transmits data and/or commands toactive nodes in sectors 211, 212 and 213.

Controller 101 can establish ad-hoc communication sessions with theother controllers, e.g., controllers 102 and 103—using an automateddiscovery mechanism. In one embodiment, there is no pre-configurationrequired for data exchanges between controllers.

A control application is provided, that may reside in one or morecontrollers and be executed by one or more controllers to initiate aprocess for controlling the topology of network 100. The controlapplication may reside in one or more controllers, and is executed toperform one or more of the methods described herein, including affectingcommunication between controllers, sending topology information andconfiguring the controllers to reflect configured and/or changedtopologies.

In one embodiment, each sector is recognized by the control applicationas a controller instance. Furthermore, in those substations havingmultiple feeders, and thus multiple sectors, the control application mayrepresent the controller in that substation as multiple “logical”controller instances. Data is then exchanged between controllerinstances as needed. As used herein, “controller instance” includes aphysical or logical controller recognized by the control application.Multiple controllers (or controller instances) may communicate amongeach other using ad-hoc auto discovered sessions and exchange data aboutthe status of their own network sector.

In the example shown in FIG. 1, controller 101 may be represented ascontroller instances 111, 112 and 113, which control sectors 211, 212and 213, respectively. Controller 102 may be represented as controllerinstances 121 and 122, which control sectors 221 and 222, respectively.Controller 103 may be represented as controller instance 131, whichcontrols sector 31. Accordingly, “controllers” such as controllers 101,102, 103 as described herein may, in some embodiments, also include anynumber of controller instances such as controller instances 111, 112,113, 121, 122, 131. Where high availability is necessary, applicablecontrollers may be deployed in redundant configurations.

In one embodiment, the control application generates and/or includesconfiguration data describing the network layout or topology. In oneembodiment, the configuration data describes the configuration of thenetwork as simple individual segments and nodes. As referred to herein,a controller configuration may refer to the configuration dataassociated with the controller that describes a topology, pre-configuredor otherwise, of the sector. The controller's configuration may includedata identifying nodes and/or segments, describing the relativepositions of nodes and/or segments within the sector and/or describingthe status of the nodes and/or segments within the respective sector.This configuration data may be converted by the control application (ora configuration tool therein) into dynamically sized, multi-dimensionalarrays that store the configuration information. In one embodiment, thecontrol application describes the network layout or topology by storingconfiguration data as array elements corresponding to each node andsegment in the network. This may be performed sequentially for eachsector in the network. Each node and sector are thus described in thearray as configured array data, and various characteristics orproperties of each node and sector are described in the associated arrayelement.

The control application may also record real time data from fielddevices (e.g. active nodes) and build sets of arrays as placeholders.This data may be referred to as “run time array data”. By parsing therun time array data in reference to the configured array data, thecontrol application can determine appropriate routing methods for powerto the grid's segments (single or multiple phase). When grid limits arereached, i.e., the control application has described the configurationand run time data for all nodes associated with the respective sector,the control application will inform adjacent applications running inother controllers, so that the entire network grid is described in thearray in an expandable form.

In one embodiment, a configuration data array in a controller instanceincludes data elements describing a network sector associated with thecontroller instance and the respective feeder, and each node in an orderbeginning at the breaker (“root”) and ending at the edge nodes of thesector, until all normally open switches are reached for that feeder(all “edges”).

Using the above approach, any type of network and/or sector layout ortopology may be accurately described in very simple terms. Also, thelayout of each sector may be described in identical code among allcontroller instances.

In one embodiment, the control application may use the configured arraydata to build data arrays as part of the controller's configuration(i.e., configuration data) describing the characteristics of eachnetwork component. Such arrays allow for a limitless number ofinterconnecting ties, segments, feeders or substations. Description ofthe configuration of a network can be achieved by simple description ofthe network sector topologies associated with each controller instance.Each controller instance does not need to know the configuration ofother sectors.

In one embodiment, normally open switches (i.e., edge nodes) areconfigured with the same name in adjacent controller instances, so thatwhen referenced by name, either controller instance will address eachnormally open switch correctly. This common naming convention allows foreach controller to easily and accurately identify the normally openswitches referenced in requests among the controllers.

In one embodiment, each of the controllers includes a respective dataarray. A controller's data array or other stored description of thetopology of its respective sector, may be referred to as part of a“controller configuration”. “Configuration information” refers to datastored with the controller, and may include all or part of thecontroller's data array. Configuration information includes datadescribing the stored and/or detected topology of a controller'srespective sector. In one embodiment, the configuration information isstored with the controller in the form of a data array, which includes aunique identifier of each node in the sector controlled by thecontroller.

Dynamic changes in sectors' topologies (configurations) belonging to onecontroller instance will require updating of the configurations in othercontroller instances, so that automation functions continue to operateas configured for the initial sector topology.

In one embodiment, the controllers will establish ad-hoc communicationswith one another, based on auto discovery methods, to share arrayelements part of the configuration information, such as the topology ofat least a portion of their respective sectors and/or configuration datarelated to one or more nodes within the controller's sector.

In one embodiment, a trigger controller is a controller instance thathas been affected by a change in the power network topology. Changes innetwork topology include any condition that has caused power to flow toa segment or node from a feeder associated with a network sector notpreviously associated with the segment or node. In this instance, thisaffected segment or node is receiving power from a feeder associatedwith a new network sector, and thus the affected segment or node is nowassociated with a new network sector. Examples of such changes, referredto as “triggers”, include the addition of new network controllers, nodesor segments, a commanded change of state, a change in status of anynodes resulting in new normally open ties, and sectionalization andreconfiguration processes resulting from a network fault.

In one embodiment, a trigger controller dynamically issues a broadcastmessage to all other controllers, to inform them of a change in thetrigger controller's respective topology. The broadcast is not limitedto the form of a broadcast as understood in internet protocol networks.The broadcast message allows for self-discovery prompting an ad-hocresponse from other controllers without requiring prior mutualknowledge.

In one embodiment, the broadcast message includes an identification ofone or more affected segments or nodes of the trigger network sector,which include one or more nodes whose connection with the power sourcehas been lost or otherwise dropped. The affected sector may also includenew normally open ties such as ties that were normally closed in theprevious topology but whose state has been changed to normally open inthe current topology. Such affected segments may be disconnected fromall power sources as a result of the topology change, or may beconnected with a new sector/power source due to the topology change.

Identification of the affected segments may include a unique identifierof each affected segment, for example, an identifier associated with aconfiguration data array such as the array described above. Theidentifier may uniquely identify nodes whose power supply has been lostor changed and/or nodes whose status has been changed to that of anormally open tie as a result of the topology change.

In one embodiment, the broadcast message includes a copy of at least aportion of the trigger controller instance's stored data arraycontaining only changed array elements, that describes one or moreaffected nodes or segments in the controller's sector. In oneembodiment, the broadcast message includes an indication of a change inthe trigger controller's sector and/or data (such as a uniqueidentifier) describing one or more nodes that have been affected by thesector change.

All other controllers (and their instances) in the network will acceptthe broadcast message from the trigger controller instance, anddetermine whether the identified affected segment (in the form of, forexample the changed array element referenced by the unique identifier)is under its control and connected to its associated power source. Inone embodiment, in response to the broadcast message, and if anidentified affected segment is under the control of or otherwiseassociated with another controller instance (referred to herein as an“affected controller”), the affected controller and the triggercontroller will establish an ad-hoc unicast or other point-to-pointcommunication session therebetween based on the broadcast message sourceparameters (address). Configuration information may then be exchangedbetween the trigger controller and one or more affected controllers viathe ad-hoc communication sessions. For example, the trigger controllersends configuration data (array elements) relating to affected segmentsto the affected controller(s).

In one embodiment, the communication session is established by eachcontroller without any knowledge of other controllers in the systemprior to the topology change. Multiple communication sessions can beestablished to enable communication between the trigger controller andmultiple affected controllers.

Each controller may use the trigger configuration information to confirmand/or identify the nodes located within the controller's respectivesector as a result of the topology change. For example, a controller canidentify nodes and network segments that are under its own control orconnected to its respective feeder, but not previously configured in itsown data array or other configuration data. Likewise, the triggercontroller can identify nodes and network segments that are no longerunder its control, but were previously configured in its own data array.The controllers can thus update their own configuration data to reflectthe current topology or topologies of their respective sectorsautomatically based on configuration data sent from one or more triggercontrollers.

The configuration information used to update the other affectedcontroller's configuration may be configuration data sent in thebroadcast message and/or the established ad-hoc communication session inform of array elements. For example, identification information in theform of a unique identifier is sent with the broadcast message to allowthe other controllers to determine whether any of the affected segmentsare within their sector, and additional trigger controller configurationdata is sent via the ad-hoc unicast or other communication session toallow the affected controller to update it's configuration data (arrayelements). Examples of additional configuration data include node type,relative position in relation to other nodes and segments and otherinformation found in the trigger controller's configuration data.

In one example, in response to a change in topology of the network, anaffected or trigger controller sends a broadcast message including anidentification of affected segments to other controllers in the network.For example, a newly added controller is deployed in a substation andconfigured to control a segment of the network and configured to controla “newly added sector”. The newly added sector may include new networksegments and/or network segments previously under the control of one ormore other controllers. The newly added controller may send a broadcastmessage including its configuration information, such as the addressesof its normally open ties. The other pre-present controllers receive themessage and compare their respective configurations to the newly addedconfiguration to determine whether the configuration of their respectivesectors has changed. In this way, all controllers (and their instances)can automatically configure themselves without the need for anypre-configuration procedures or user intervention.

There is no single master controller in the systems and methodsdescribed herein. In the case of simultaneous faults or other conditionsthat affect multiple sectors, there may be multiple controllers actingas “trigger controllers”.

The exchange of information between controllers occurs ad-hoc (“on thefly”) and without previous knowledge of each other. Controllers needonly have initial knowledge of their own sectors and need not haveglobal knowledge, i.e., knowledge of other network sectors.

FIG. 2 illustrates an instance in which a power network topology ischanged. The example shown in FIG. 2 illustrates a change in networktopology due to a fault detection and restoration operation. However,the topology change may result from any number of reasons, such as anoperator-controlled change, or an addition or subtraction of one or morenetwork devices, controllers or sectors.

In the case of a fault in a given segment, the trigger controller is atleast one controller instance that controls at least a portion of thefaulted sector, i.e., the sector that includes the faulted segment. Thetrigger controller may isolate the fault, then look for possibilities ofrestoring the power from the same substation, or from other substations,by inquiring as to the power availability and circuit capacityrestrictions of the remaining controller instances, via the broadcastand ad-hoc combination of self discovered communication sessions. Theother controllers become an active part of the control applicationprocess after receiving requests from the trigger controller.

With reference to FIG. 2, if a fault occurs in sector 211, for example,between nodes 318 and 321, the resulting power network topology may bethe topology shown in FIG. 2, wherein ties 317, 319 and 321 are open (toisolate the fault), tie 337 is closed and tie 323 remains open toprovide power to the edge segments previously part of sector 212, butnow part of an extended sector 230′. Tie 312 is closed to provide powerto a now extended sector 211′.

FIG. 3 illustrates a method 400 of controlling a multi-feed powerdistribution network by configuring and/or re-configuring controllerinstances in a power network. The method 400 includes one or more stages401-407. Although the method 400 is described in conjunction with thesystem 100, the method 400 may be used with any system capable ofcommunication between network sectors as described herein. In oneembodiment, the method 400 includes the execution of all of stages401-407 in the order described. However, certain stages may be omitted,stages may be added, or the order of the stages changed.

In the first stage 401, a first controller detects a change in topologyof a respective first network sector. In this example, the firstcontroller is a trigger controller instance 112 that detects andisolates a fault between nodes 317, 319 and 321, shown in FIG. 2. Thenew network topology resulting from the fault is shown in FIG. 2. Thetrigger controller may refer to any controller that experiences atopology change (e.g., a change in the normally open tie), and is notlimited to that described herein. In addition, the change in topologymay occur due to any reason, which is not limited to a fault.

In this example, as a result of the topology change, the triggercontroller 112 is now associated with a modified or affected networksector 212′. The affected nodes in this example are nodes 317-323 and337. The controller 112, as a result of the topology change, is limitedby node 317, which is now a normally open tie, and no longer has controlover nodes 318-323 and 337. Other controller instances must now coverthe remaining nodes delimited by 319,320,312, and 321,322,323,337.

In the second stage 402, the trigger controller instance 112 sends abroadcast message to all other controllers instances indicating that thenetwork sector 212′ has changed, specifying the unique identifiers ofthe previously configured normal open ties, now being out of reach. Inone embodiment, the trigger controller 112 sends a broadcast messageincluding the unique identifiers of the normal open ties 312, 337 and323. The broadcast message may include various types of configurationdata, such as data array elements with addresses, numbers, and settings.

Each controller instance 111, 113, 121, 122 and 131 receives thebroadcast message and compares the received normal open ties' uniqueidentifier configuration data to its respective sector normal open tieidentifiers (edges) to determine whether its own respective sectorincludes one or more of the communicated normal open tie nodes, and thecontroller instance needs to become an “affected” controller instance.In the present example, the controller instance 111 detects that node312 is now closed and linked to devices located past node 312, and thecontroller instance 111 becomes an affected controller instance. Thecontroller instance 131 detects that node 337 is now closed and linkedto devices located past 337, and 131 becomes an affected controllerinstance. The sector 211 topology in this example has changed and isreferred to as affected sector 211′, with an increased coverage. Thesector 230 topology in this example has changed and is referred to asaffected sector 230′, with an increased coverage. The sector 212topology in this example has changed and is referred to as affectedsector 212′, with a decreased coverage.

In the third stage 403, a unicast session or other communicationexchange mechanism is established between the trigger controller and oneor more affected controller instances, such as 111 and 131. In oneembodiment, multiple unicast sessions may be established in parallelwith different controller instances as required, to service multiplepower sources. In the present example, controller instance 111 requestsand establishes an ad-hoc unicast session with the broadcasting(trigger) controller instance 112 and sends an acknowledgement or otherreply to controller instance 112 identifying node 312 as being part ofits own configuration and requests the data defining the new topology,and controller instance 131 requests and establishes an ad-hoc unicastsession with the broadcasting (trigger) controller instance 112 andsends an acknowledgement or other reply to controller instance 112identifying node 337 as being part of its own configuration and requeststhe data defining the new topology.

In the fourth stage 404, using the established ad-hoc unicast sessionsin 403, and based on the provided data identifiers received from theother controller instances, the trigger controller instance pushes orsends configuration data associated with network segments that are nolonger part of its coverage or control or otherwise no longer associatedwith the trigger controller's sector, to the requesting affectedcontroller instances. In this example, the trigger controller instance112 sends to 111 configuration information data relating to nodes 319,320 and segments in between—because the node 312 identifier has beenreceived from controller instance 111. The trigger controller instance112 sends to 131 configuration information data relating to nodes 321,322, 323 and segments in between—because the node 337 identifier hasbeen received from controller instance 131.

After receiving the configuration information data, the affectedcontrollers dynamically (“on the fly”) re-configure themselves such thattheir control reach will be extended, with the normal open tie(s) now ina different location. In this example, the controller instance 111 has anew normally open tie 319, and the controller instance 131 has two newnormally open ties 321, 323. In this example, the affected controller111 detects that switch 312 is closed and nodes 312, 320, 319 andsegments in between are under its control. The affected controller 131detects that switch 337 is closed and nodes 321, 322, 323, 337 andsegments in between are under its control. The controller 111 updatesits data arrays to include configuration data (e.g., array elements)sent from the trigger controller 112. The controller 111 now isconfigured to control a new sector 211′. The controller 131 updates itsdata arrays to include configuration data (e.g., array elements) sentfrom the trigger controller 112. The controller 131 now is configured tocontrol a new sector 230′. The new resulting configuration can betreated no differently then an equivalent pre-built configuration, butwas all a result of dynamic calculations and data exchanges, based onreal time data. In one embodiment, the controller instances 111, 131 andthe trigger controller 112 save their previous respectiveconfigurations, e.g., previously configured data arrays, for future use,to be able to restore their respective sector topologies to reflect aprevious configuration in the instance that the network sectors arerestored to the topology existing before the topology change, such as abase topology.

In one embodiment, affected nodes or segments now have a new controller,i.e., the affected controller. For example, the nodes 319 and 320 nowhave a new controller 111, and the nodes 321, 322 and 323 now have a newcontroller 131. In one embodiment, however, nodes 319, 320, 321, 322 and323 will continue to operate via pre-configured communications protocolsexisting prior to the topology change, i.e. to the controller instance112.

In the fifth stage 405, the trigger controller configures itself toroute all real time data traffic associated with affected nodes to theaffected controller instances, via the ad-hoc unicast communicationssessions established in stage 403, in both directions, and all newlyconfigured (affected) controller instances configure themselves to usethe ad-hoc unicast communication sessions established in stage 403 toaccept the routed real time data traffic coming from the triggercontroller. As a result, all the real time databases of affectedcontroller instances are up to date with affected node data, indirectlyvia the trigger controller and no differently then an equivalentpre-built configuration. In one embodiment, the controller instance 111communicates indirectly with the new nodes 312 and 319 (320 is passive)via the trigger controller 112, which in turn communicates with thenodes 312 and 319 via pre-configured communications protocols, and thecontroller instance 131 communicates indirectly with the new nodes 321and 323 (322 is passive) via the trigger controller 112, which in turncommunicates with the nodes 321 and 323 via pre-configuredcommunications protocols. In this way, pre-existing communicationprotocols between controllers and nodes in the network do not need to bemodified to reflect the configuration changes.

For example, each controller instance 111, 131 and 112 includes dynamicdata arrays reflecting the new configuration of their respective sectors211′, 230′ and 212′. The trigger controller 112 still receivescommunications and/or signals from the nodes 319, 321, 323 based on thepre-configured protocols, and relays the signals to the affectedcontroller instances 111, 131 based on its own data array. Likewise,communications from the affected controller instance 111 to the new node319 are relayed through the trigger controller 112, and communicationsfrom the affected controller instance 131 to the new nodes 321, 323 arerelayed through the trigger controller 112. This configurationeliminates the need for the affected controller instances to have anyknowledge of individual devices in the original trigger sector; theaffected controllers only need to use the newly learnt triggercontroller 112 as a dynamically established proxy for real time dataaccess to the affected nodes part of the original sector.

In the sixth stage 406, the entire system runs with the new self-createdcontroller instances and trigger controllers acting as if they have beenpreconfigured with the sectors 211′, 230′ and 212′ and will be capableof accepting future triggers (see action 401 to 406 in FIG. 3). Themethod 400 can be repeated for future triggers, causing the automaticcreation of additional modified sectors, all without any user (e.g.,human) required deployment of new configurations, and without any needof the controllers to have prior knowledge of each other. In oneembodiment, the method 400 may be repeated until reaching apre-determined number (threshold) of operations, or until availablepower flow paths are exhausted.

In the seventh stage 407, in the instance that power network topologiesrevert to the previous configurations (e.g., 211′ reverts to 211, 230′reverts to 230 and/or 212′ reverts to 212) due to, for example, operatorinitiated actions, the controllers 111, 131 and 112 may automaticallyrevert back to their previous or base configurations, without requiringany user intervention. In one embodiment, the controllers can beequipped with pre-programmed automatic sequences, which will restore thepower network topology to normal, upon a single initiated command acrossthe network. For example, in the instance that the network sectors 211′,230′ and 212′ are reverted back to their previous topologies (i.e.,configured as sectors 211, 230 and 212), each controller 111, 131 and112 reconfigure their respective data arrays based on a configurationthat was saved in memory prior to changing the data arrays to reflectthe topology change. In one embodiment, by continuously monitoring theactual power network topology, the controllers are capable ofautomatically identifying changes in topology and/or identifying when aprevious topology has been restored, and automatically reverting back toprevious configuration settings. All ad-hoc unicast communicationsessions may be closed after reverting to the initial states.

The network 100 may be in communication with one or more remote controlcenters. In such an embodiment, each controller may inform the remotecontrol center of what is being performed at any moment. For example,each controller instance may use an appropriate number of analog encodedvalues (“pseudo points”) to inform the remote control center of what isbeing performed. Each state and stage of the control application mayhave unique associated values updated in real time in these analogpseudo points. Furthermore, each controller instance may accept commandsfrom the control center, such as “reset”, “inhibit”, “safety tagapplied”, “under maintenance” and others. In one embodiment, eachcontroller instance may create events for important states, which may berelayed to the user and/or control center.

A number of advantages, and technical contributions accrue from theabove-disclosed embodiments, some of which are discussed below. Forexample, a technical effect includes allowing for the dynamic, real-timeconfiguration of mid level hierarchy controllers in a power network,without the need for manual or outside configuration, and without theneed of field nodes controllers (the low level hierarchy in the powernetwork) to be supplied from the same family, or required to have commonsets of function, or any other prescriptive restriction. In theabove-disclosed embodiments, the field nodes controllers can be of anytype, function, family, vendor, communication protocol, with no imposedrestrictions. Operation restrictions are reduced, as the methods andsystem allow the network to respond to multiple faults or other topologychanges without the need for outside intervention.

In addition, the systems and methods provide the technical effect ofallowing for mid level hierarchy controller re-configuration andoperation of changed sector without the need to modify pre-existingcommunications protocols. There is no need to pre-configure multiplecombinations of data channels or paths, as the system is configured toautomatically learn how to route data based on learned real-timeconfigurations. In addition, there is no need for complicated manualprocedures to either restore or to confirm restoration of the powernetwork topology back to normal. The systems and methods describedherein do not require centralized distribution management systems (DMS),nor associated specific skilled personnel. The systems and methods arefield device (low level hierarchy) and communication medium transparent,allowing for multi-vendor field equipment to co-exist together.

Additional advantages and technical effects include allowing for modulardeployment of additional nodes, sectors and control units, allowingsystems integrators to focus on the current and future needs, withoutconcern for what has been already configured or commissioned, andallowing quick routing self learning and the use of standard IT (VLAN)technologies. Other advantages include savings associated with reducedneed for field crew work (e.g., testing, commissioning, maintenance) andindependency of communication protocols and mediums to field devices andtheir types.

While the methods and systems described above and/or claimed herein aredescribed above with reference to an exemplary embodiment, it will beunderstood by those skilled in the art that various changes may be madeand equivalence may be substituted for elements thereof withoutdeparting from the scope of the methods and systems described aboveand/or claimed herein. In addition, many modifications may be made tothe teachings of above to adapt to a particular situation withoutdeparting from the scope thereof. Therefore, it is intended that themethods and systems described above and/or claimed herein not be limitedto the embodiment disclosed for carrying out this invention, but thatthe invention includes all embodiments falling with the scope of theintended claims. Moreover, the use of the term's first, second, etc.does not denote any order of importance, but rather the term's first,second, etc. are used to distinguish one element from another.

The invention claimed is:
 1. A system for controlling a multi-feed powerdistribution network, the network including a first network sector andat least one second network sector, the system comprising: a firstcontroller configured to control operation of the first network sectorof the multi-feed power distribution network, the first network sectorincluding a first plurality of devices connected to a first powersource, and the first controller including first configuration datarepresenting a first network sector topology, the first controllerconfigured to, in response to a topology change in the first networksector causing a change in a location from which power is supplied to atleast one affected network segment, transmit a message identifying theat least one affected network segment from the first controller to thenetwork without prior knowledge of any other controllers; at least onesecond controller configured to control operation of the at least onesecond network sector of the multi-feed power distribution network, theat least one second network sector including a second plurality ofdevices connected to a second power source, and the at least one secondcontroller including second configuration data representing a secondnetwork sector topology, the second controller configured to receive themessage without prior knowledge of any other controllers, exchangeconfiguration information regarding the at least one affected segmentwith the first controller, and automatically update the secondconfiguration data of the second controller based on the configurationinformation received from the first controller to reflect the topologychange.
 2. The system of claim 1, wherein each of the first controllerand the at least one second controller are controller instances selectedfrom at least one of a physical controller and a logical controller. 3.The system of claim 1, wherein the at least one second controller is aplurality of second controllers.
 4. The system of claim 1, wherein thetopology change is selected from at least one of: a change in aconnection from at least one device between the first power source andthe second power source, a fault in the network, an addition of at leastone device to the network, and a subtraction of at least one device fromthe network.
 5. The system of claim 3, wherein the first controller andthe at least one second controller are configured to automaticallydiscover and automatically configure themselves based on one or morebroadcast messages sent from the first controller to the plurality ofsecond controllers.
 6. The system of claim 1, wherein exchangingconfiguration information includes establishing an ad-hoc automated andself discovered unicast session between the first controller and the atleast one second controller and sending configuration data related tothe affected segments from the first controller to the at least onesecond controller.
 7. The system of claim 5, wherein exchangingconfiguration information includes establishing an ad-hoc automated andself discovered unicast session between the first controller and the atleast one second controller and sending configuration data related tothe affected segments from the first controller to the at least onesecond controller.
 8. The system of claim 1, wherein the firstcontroller and the at least one second controller are configured torevert the first and second configuration data to a base configurationin response to a restoration of the first and second network sectortopologies to base topologies.
 9. The system of claim 1, wherein thefirst configuration data includes a first data array for the firstnetwork topology, the first data array including a first plurality ofarray elements, each of the first plurality of array elementsrepresenting properties of one of the first plurality of devices, andconfiguration information includes at least one data array elementdescribing the affected network segment.
 10. The system of claim 1,wherein the second configuration data includes a second data array forthe second network sector, the second data array including a secondplurality of array elements, each of the second plurality of arrayelements representing properties of one of the second plurality ofdevices, and updating a configuration of the at least one secondcontroller includes incorporating the at least one data array element inthe second data array.
 11. A method of controlling a multi-feed powerdistribution network including a plurality of devices, the networkincluding a first network sector that includes a first plurality ofdevices connected to a first power source and at least one secondnetwork sector that includes a second plurality of devices connected toa second power source, the method comprising: in response to a topologychange in the first network sector controlled by a first controllerincluding first configuration data representing the first network sectortopology, the topology change causing a change in a location from whichpower is supplied to at least one affected network segment, transmittinga message identifying the at least one affected network segment from thefirst controller to the network without prior knowledge of any othercontrollers; receiving the message by at least one other controllerconfigured to control the at least one second network sector, withoutprior knowledge of any other controllers, the at least one othercontroller including second configuration data representing the secondnetwork sector topology; exchanging configuration information regardingthe at least one affected segment between the first controller and theat least one other controller; and automatically updating the secondconfiguration data of the at least one other controller based on theconfiguration information received from the first controller to reflectthe topology change.
 12. The method of claim 11, wherein the affectedsegment includes at least one device selected from at least one of: anactive node, a passive node, a controllable switch, a recloser, acircuit breaker, a network split, and a sensor.
 13. The method of claim11, wherein the topology change is selected from at least one of: achange in a connection from at least one device between the first powersource and the second power source, a fault in the network, an additionof at least one device to the network, and a subtraction of at least onedevice from the network.
 14. The method of claim 11, wherein the atleast one other controller includes a plurality of other controllers,and the message is a broadcast message sent from the first controller toeach of the plurality of controllers.
 15. The method of claim 11,wherein exchanging configuration information includes determining by theat least one other controller whether the at least one affected segmentis included in the second network sector as a result of the topologychange, and in response to the at least one affected segment beingincluded in the second network sector, establishing an ad-hoc automatedand self discovered unicast session between the first controller and theat least one other controller and sending configuration data related tothe affected segments from the first controller to the at least oneother controller.
 16. The method of claim 14, wherein exchangingconfiguration information includes determining by the at least one othercontroller whether the at least one affected segment is included in thesecond network sector as a result of the topology change, and inresponse to the at least one affected segment being included in thesecond network sector, establishing an ad-hoc automated and selfdiscovered unicast session between the first controller and the at leastone other controller and sending configuration data related to theaffected segments from the first controller to the at least one othercontroller.
 17. The method of claim 11, wherein the first controller andthe at least one other controller is configured to revert the first andsecond configuration data to a base configuration in response to arestoration of the first and second network sector topologies to basetopologies.
 18. The method of claim 11, wherein the first configurationdata includes a first data array for the first network sector, the firstdata array including a first plurality of array elements, each of thefirst plurality of array elements representing properties of one of thefirst plurality of devices, and the configuration information includesat least one data array element describing the at least one affectednetwork segment.
 19. The method of claim 18, wherein the secondconfiguration data includes at least one second data array for thesecond network sector, and updating a configuration of the othercontroller includes incorporating the at least one data array element inthe at least one second data array.
 20. The method of claim 19, furthercomprising: saving, by the first controller, a copy of the first dataarray reflecting a first base topology of the first network sector priorto the topology change; and saving, by the at least one othercontroller, a copy of the second data array reflecting a second basetopology of the at least one second network sector prior to the topologychange.